Pierrefonds Castle in Picardie (Picardy), France. Rebuilt during the 19th. century by Viollet-le-Duc, it is mostly a reinterpretation of what would have been a medieval castle... adapted to the19th century way of life of the emperor Napoleon III who ordered the work.
The Kermario Dolmen at Carnac, Brittany, Northern France. The more than 3,000 prehistoric standing stones were hewn from local rock and erected by the pre-Celtic people of Brittany, and are the largest such collection in the world. The stones were erected at some stage during the Neolithic period, probably around 3300 BC, but some may date to as old as 4500 BC.